Well, I ended up buying one from a local B&M for RRP and it included the new 'dot-cap'. I've never owned a petri before, nor do I have any previous experience with 'old-school' fixed AF RDAs that typically get brought up when discussing the petri.
I am very impressed with the quality of the RDA overall, I've found no machining flaws and the fit and finish is top notch. I find the airflow to be perfect for me. Building has been relatively easy. Performance is good, not great, but I need to experiment with coil diameter and placement as I believe placement is the key to modulating how the RDA vapes.
My one serious, huge, frustrating con - it whistles... Doesn't matter if I take a slower inhale or pull as hard as I can...it whistles. Luckily my fiancé is out of town so she can't complain about the noise, but I am driving my dogs crazy each time I vape, and I'll be next to go crazy. I'm extraordinarily hesitant to attempt to modify the barrel given the price of the RDA. I don't know if it's even worth my while to email dotmod about the issue...